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		<title>three.js webgl - materials - HDR texture loader</title>
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		<link type="text/css" rel="stylesheet" href="main.css">
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		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - webgl HDR (RGBE) texture loader example<br/>
			Image courtesy of <a href="http://www.pauldebevec.com/Research/HDR/" target="_blank" rel="noopener">Paul Debevec</a>.
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import { GUI } from 'three/addons/libs/lil-gui.module.min.js';

			import { HDRLoader } from 'three/addons/loaders/HDRLoader.js';

			const params = {
				exposure: 2.0
			};

			let renderer, scene, camera;

			init();

			function init() {

				renderer = new THREE.WebGLRenderer();
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				document.body.appendChild( renderer.domElement );

				renderer.toneMapping = THREE.ReinhardToneMapping;
				renderer.toneMappingExposure = params.exposure;


				scene = new THREE.Scene();

				const aspect = window.innerWidth / window.innerHeight;

				camera = new THREE.OrthographicCamera( - aspect, aspect, 1, - 1, 0, 1 );

				new HDRLoader()
					.load( 'textures/memorial.hdr', function ( texture, textureData ) {

						//console.log( textureData );
						//console.log( texture );

						const material = new THREE.MeshBasicMaterial( { map: texture } );

						const quad = new THREE.PlaneGeometry( 1.5 * textureData.width / textureData.height, 1.5 );

						const mesh = new THREE.Mesh( quad, material );

						scene.add( mesh );

						render();

					} );

				//

				const gui = new GUI();

				gui.add( params, 'exposure', 0, 4, 0.01 ).onChange( render );
				gui.open();

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				const aspect = window.innerWidth / window.innerHeight;

				const frustumHeight = camera.top - camera.bottom;

				camera.left = - frustumHeight * aspect / 2;
				camera.right = frustumHeight * aspect / 2;

				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

				render();

			}

			//

			function render() {

				renderer.toneMappingExposure = params.exposure;

				renderer.render( scene, camera );

			}

		</script>
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